/*----------------------------------------------------------------------------
 * Tencent is pleased to support the open source community by making TencentOS
 * available.
 *
 * Copyright (C) 2019 THL A29 Limited, a Tencent company. All rights reserved.
 * If you have downloaded a copy of the TencentOS binary from Tencent, please
 * note that the TencentOS binary is licensed under the BSD 3-Clause License.
 *
 * If you have downloaded a copy of the TencentOS source code from Tencent,
 * please note that TencentOS source code is licensed under the BSD 3-Clause
 * License, except for the third-party components listed below which are
 * subject to different license terms. Your integration of TencentOS into your
 * own projects may require compliance with the BSD 3-Clause License, as well
 * as the other licenses applicable to the third-party components included
 * within TencentOS.
 *---------------------------------------------------------------------------*/

#include "tos_k.h"

#if TOS_CFG_SEM_EN > 0u

__API__ k_err_t tos_sem_create_max(k_sem_t *sem, k_sem_cnt_t init_count,
		k_sem_cnt_t max_count)
{
	TOS_PTR_SANITY_CHECK(sem);

	if (unlikely(init_count > max_count))
	{
		init_count = max_count;
	}

	sem->count = init_count;
	sem->count_max = max_count;

	pend_object_init(&sem->pend_obj);
	TOS_OBJ_INIT(sem, KNL_OBJ_TYPE_SEMAPHORE);

	knl_object_alloc_set_static(&sem->knl_obj);

	return K_ERR_NONE;
}

__API__ k_err_t tos_sem_create(k_sem_t *sem, k_sem_cnt_t init_count)
{
	return tos_sem_create_max(sem, init_count, (k_sem_cnt_t) -1);
}

__API__ k_err_t tos_sem_create_max_dyn(k_sem_t **sem, k_sem_cnt_t init_count,
		k_sem_cnt_t max_count)
{
	k_sem_t *the_sem;

	TOS_IN_IRQ_CHECK();
	TOS_PTR_SANITY_CHECK(sem);

	if (unlikely(init_count > max_count))
	{
		init_count = max_count;
	}

	the_sem = tos_mmheap_calloc(1, sizeof(k_sem_t));
	if (!the_sem)
	{
		return K_ERR_SEM_OUT_OF_MEMORY;
	}

	the_sem->count = init_count;
	the_sem->count_max = max_count;

	pend_object_init(&the_sem->pend_obj);
	TOS_OBJ_INIT(the_sem, KNL_OBJ_TYPE_SEMAPHORE);

	knl_object_alloc_set_dynamic(&the_sem->knl_obj);

	*sem = the_sem;

	return K_ERR_NONE;
}

__API__ k_err_t tos_sem_create_dyn(k_sem_t **sem, k_sem_cnt_t init_count)
{
	return tos_sem_create_max_dyn(sem, init_count, (k_sem_cnt_t) -1);
}

__API__ k_err_t tos_sem_destroy(k_sem_t *sem)
{
	TOS_CPU_CPSR_ALLOC();

	TOS_PTR_SANITY_CHECK(sem);
	TOS_OBJ_VERIFY(sem, KNL_OBJ_TYPE_SEMAPHORE);

	TOS_CPU_INT_DISABLE()
	;

	pend_wakeup_all(&sem->pend_obj, PEND_STATE_DESTROY);

	pend_object_deinit(&sem->pend_obj);

	if (knl_object_alloc_is_dynamic(&sem->knl_obj))
	{
		TOS_OBJ_DEINIT(sem);
		tos_mmheap_free(sem);
	}
	else
	{
		TOS_OBJ_DEINIT(sem);
	}

	TOS_CPU_INT_ENABLE()
	;
	knl_sched();

	return K_ERR_NONE;
}

__STATIC__ k_err_t sem_do_post(k_sem_t *sem, opt_post_t opt)
{
	TOS_CPU_CPSR_ALLOC();

	TOS_PTR_SANITY_CHECK(sem);
	TOS_OBJ_VERIFY(sem, KNL_OBJ_TYPE_SEMAPHORE);

	TOS_CPU_INT_DISABLE()
	;

	if (sem->count == sem->count_max)
	{
		TOS_CPU_INT_ENABLE()
		;
		return K_ERR_SEM_OVERFLOW;
	}

	if (pend_is_nopending(&sem->pend_obj))
	{
		++sem->count;
		TOS_CPU_INT_ENABLE()
		;
		return K_ERR_NONE;
	}

	pend_wakeup(&sem->pend_obj, PEND_STATE_POST, opt);

	TOS_CPU_INT_ENABLE()
	;
	knl_sched();

	return K_ERR_NONE;
}

__API__ k_err_t tos_sem_post(k_sem_t *sem)
{
	return sem_do_post(sem, OPT_POST_ONE);
}

__API__ k_err_t tos_sem_post_all(k_sem_t *sem)
{
	return sem_do_post(sem, OPT_POST_ALL);
}

__API__ k_err_t tos_sem_pend(k_sem_t *sem, k_tick_t timeout)
{
	TOS_CPU_CPSR_ALLOC();

	TOS_IN_IRQ_CHECK();
	TOS_PTR_SANITY_CHECK(sem);
	TOS_OBJ_VERIFY(sem, KNL_OBJ_TYPE_SEMAPHORE);

	TOS_CPU_INT_DISABLE()
	;

	if (sem->count > (k_sem_cnt_t) 0u)
	{
		--sem->count;
		TOS_CPU_INT_ENABLE()
		;
		return K_ERR_NONE;
	}

	if (timeout == TOS_TIME_NOWAIT)
	{ // no wait, return immediately
		TOS_CPU_INT_ENABLE()
		;
		return K_ERR_PEND_NOWAIT;
	}

	if (knl_is_sched_locked())
	{
		TOS_CPU_INT_ENABLE()
		;
		return K_ERR_PEND_SCHED_LOCKED;
	}

	pend_task_block(k_curr_task, &sem->pend_obj, timeout);

	TOS_CPU_INT_ENABLE()
	;
	knl_sched();

	return pend_state2errno(k_curr_task->pend_state);
}

#endif // TOS_CFG_SEM_EN

